HIV drug resistance can be managed

24th July 2012

The HIV virus is beginning to show signs of resistance to antiretroviral drugs used to treat it, but the problem is a manageable one, according to the World Health Organisation (WHO).

The growing use of ARVs in poorer and middle-income countries has led to resistance to some therapies, the WHO warned, but the problem is not as acute as it was in richer countries when the drugs first appeared on the market.

The WHO published a new report into HIV drug-resistance as global experts congregated in Washington for the International AIDS Conference, which has gathered more than 20,000 scientists, activists and policymakers to work on a road-map to beat the HIV epidemic.

Experts said they hope to begin to “turn the tide” of the epidemic, using some powerful tools already in hand.

The wider availability of life-saving drugs at affordable prices in recent years has meant that around eight million people are now taking ARVs in low- and middle-income countries: that number was just 400,000 in 2003.

The WHO report said that 6.8% of HIV showed ARV resistance in 2010, compared with resistance rates of 8-14% in higher-income countries at a comparable stage in the development of treatment programmes.

It cited good programme management as crucial to keeping levels of drug resistance down in poorer countries, as well as simpler combinations of drugs than the cocktails people first began taking in richer countries during the 1990s.

According to Gottfried Hirnschall, director of WHO’s HIV department, the agency now needed to focus on ensuring that drug resistance remained limited and manageable.

Natural mutations of a virus can give rise to drug resistance, but it can mostly be prevented by strict adherence to treatment with no interruptions and all the right pills taken at the right time.

Hirnschall's colleague Joseph Perrïens said healthcare professionals needed to focus on ensuring people took the right medications, and that they continued to take them.

A simple regime, a reliable supply and close monitoring of patients by healthcare professionals were the key to success, he said.

As many as 38% of patients treated in poorer countries lose contact with healthcare providers after they have been diagnosed and given a prescription, surveys show.

Such loss of contact is one of the main causes of drug resistance.

WHO called on clinics providing antiretroviral treatment to set up "early warning indicators" to identify and address factors that could cause drug resistance.

Patients undergoing treatment should also be monitored after 12 months to see how the virus is responding to the ARV therapy, it said.